Résumé
In Thailand, rice producers are receiving government support (input subsidies, guarantee of prices or revenues, free water for irrigation, etc.). This is understandable because under open-market conditions, rice cultivation is providing important services to society but it generates low and risky income to rice farmers. Besides providing marketable products, rice production maintains landscapes and social coherence in the rural areas. It also influences the water cycle: e.g. drought or flood management, and rice fields can produce some functions close to those of natural wetlands if good agricultural practices are followed. Although potentially very important for society, some of these functions are not exchanged on markets; hence, rice farmers are providing them free of charge. Without markets, the society's demand and WTP for these functions is not easily known. To address this challenge, we conducted a study in the province of Nakhon Ratchasima in Northeastern Thailand. Four broad categories of functions, namely economic (providing food and income), social (e.g. providing employment in rural areas), environmental (e.g. habitat for birds) and cultural functions (e.g. maintaining traditional way of life) were identified during focus groups. 300 persons with contrasted socio-economic characteristics were asked to rank their preferences using AHP, and were submitted to a choice experiment (CE) to evaluate their WTP. We found that the population gave the highest weight to the economic and market functions of irrigated areas. The average weights of non-market functions were much higher than initially expected. Social and environmental functions received an average weight of 0.27 (out of a maximum of one) while the economic functions received a weight of 0.33. Cultural values are ranking much lower (0.12). In fact, these average figures are hiding an important diversity in the ordering of priorities: three categories of population were identified after their differentiated function rankings: the "eco-centered", the "environmentalists", and the "socially concerned" that probably push for different policies. Choice experiments results showed that these rankings are consistent with the population WTP for these functions. Some part of the Thai society is recognizing that irrigated agriculture is providing more goods and services than only food products. As such, this could justify financial support from Government to irrigated areas. However, this also means that financial transfers to irrigated areas should not be given without conditions attached to them as is presently done. A mechanism that link financial support to completion of certain practices positively correlated to those functions could be developed. (Résumé d'auteur)